On Sept. 14, "The Jay Leno Show" will debut on NBC—the first live comedy show in decades to air at 10 p.m., a lucrative slot typically reserved for expensive dramas.

Even for TV's most famous workhorse, Mr. Leno has been clocking hours. He arrives at NBC Burbank studios at 8 a.m., an hour before anyone else. He spends his days involved in details like designing the seating layout for the new studio. To tune his act, he has done almost weekly stand-up performances at the Mirage Hotel & Casino in Las Vegas and the Comedy and Magic Club in Hermosa Beach, Calif., as well as free shows in Detroit and Wilmington, Ohio, that attracted as many as 20,000 people each. It is all part of his plan to woo as many constituents as he can —audiences, network executives and local NBC affiliates. He runs four miles a day and has lost 12 pounds in the past couple of months.

In Boston one recent afternoon, more than 1,000 people packed the Majestic Theater, run by Mr. Leno's alma mater Emerson College, to watch him perform. Mr. Leno got big laughs with a series of jokes about why women love cats, why men must dominate the remote control, and the obesity rate ("When did meat become a condiment?"). He drew howls from the crowd with a riff about the warnings on prescription medication. "Could bring on gambling and increased sexual desire," he said about a drug designed to curb restless legs syndrome or RLS. "Look honey, I'm not tapping my foot any more. Oh, I'm a horny degenerate gambler. I lost a house and committed adultery, but look at my leg."

Jay Leno's Laughline

Deb Stoddard, a 60-year-old retiree from Natick, Mass., won free Leno tickets by testing out a Sealy Posturepedic mattress at local chain Bernie & Phyl's Furniture. "I don't like the edgy comics out there," she said. Mr. Leno, she added, belongs more to "the age of Johnny Carson."

For his new show, Mr. Leno plans to seat the audience close to the stage for an intimate feel. NBC is building a track so its car-nut host can have celebrity guests race cars. Mr. Leno plans to limit musical guests to one or two nights a week. He says he learned doing the "Tonight Show" that musical acts don't attract TV audiences like they used to since fans can go to YouTube or iTunes and watch their favorite musicians whenever they like. The first show will feature Jay-Z, Rihanna and Kanye West performing together. Comedian and longtime friend Jerry Seinfeld will be Mr. Leno's first celebrity guest.

To draw younger audiences, Mr. Leno plans to feature a team of correspondents, much like Comedy Central's "The Daily Show." Correspondents will include D.L. Hughley, an actor and comedian who hosted a short-lived CNN news comedy show, reporting from Washington, MTV improv comic
Mikey Day
and
Rachel Harris,
who recently appeared in the movie "The Hangover." In one skit planned for next month, comedian
Liz Feldman
drops in at a senior citizens' center and tries to teach elderly people how to Twitter. "NBC Nightly News" anchor
Brian Williams,
who is also a part-time comedian, will also appear occasionally on the show.

In a routine from late night that he plans to continue on his new show, Mr. Leno says he doesn't go to sleep until he has completed about 60% of the following night's monologue. Each 10- to 12-minute monologue takes at least six hours to write. After each late-night show, Mr. Leno would work with his team of about 20 writers until as late as 2 a.m. on jokes for the next day.

Mr. Leno, who has a 17,000-square-foot garage, is working on a segment he calls the "green car challenge." Guest stars will be able to race around a track in a high-powered electric Ford Focus. "There are a lot of celebrities who people want to see, but they don't necessarily want to hear them talk," Mr. Leno says. (It also provides a nice spot for sponsor Ford.)

One recent Thursday morning near the NBC studios' Bob Hope Gate, where his racetrack is under construction, Mr. Leno made his pitch to publicists from PMK/HBH, a Hollywood firm that represents such stars as Matt Damon and Johnny Depp. "You put the stars in the car and see who has the fastest time," he says.

PMK/HBH says it will enlist clients to take a go around the track. Mr. Leno is "a big friend of our clients," says PMK/HBH co-chief executive Simon Halls. He added, "we're excited to explore the new show."

Live variety shows were a staple of TV programming early on, featuring entertainers like Garry Moore, Dean Martin and Carol Burnett over the years. As ratings reports became more detailed in the 1960s, networks started to take a closer look at programming. They realized older viewers and kids tune out at 10 p.m. They discovered they could charge advertisers more for commercial time during that slot because they delivered more viewers aged 18 to 49, a key television audience demographic. The networks began to integrate scripted dramas into the hour and by the 1970s were phasing out variety shows. Over the years, 10 p.m. has become known as the home of some of television's preeminent hits, such as "Dallas," "Dynasty" and "L.A. Law."

The networks "needed to go with something that is much more contemporary and appealing to young people so you started to get somewhat sexier, more adventurous or even violent stuff," says television historian Tim Brooks.

Checking Out the Competition

The 10 p.m. fall lineup on rival networks is heavy on crime dramas.

Monday

ABC 'Castle'

A comedy drama about a mystery novelist who helps the NYPD solve crimes.

CBS 'CSI: Miami'

A spinoff of the popular "CSI" police drama about forensic scientists who investigate mysterious deaths. (pictured above left)

Fox: Local news, five nights a week

ENLARGE

ABC

Tuesday

ABC 'The Forgotten'

A new drama starring Christian Slater about amateur detectives who work on murders involving unidentified victims. (above middle)

CBS 'The Good Wife'

A new drama starring Julianna Margulies as the wife of a disgraced politician played by Chris Noth. (above right)

ENLARGE

CBS

Wednesday

ABC 'Eastwick'

A new series based on "The Witches of Eastwick" by John Updike and subsequent movie about a group of women who discover their magical powers.

CBS 'CSI: NY'

A spinoff of "CSI," based in New York.

ENLARGE

CBS

Thursday

ABC 'Private Practice'

The "Grey's Anatomy" spinoff chronicles the life of Dr. Addison Montgomery after she leaves Seattle Grace Hospital for private practice.

CBS 'The Mentalist'

Crime drama about a "mentalist" who uses his feigned psychic powers and keen observational skills to solve crimes.

Friday

ABC '20/20'

Long-running weekly news broadcast.

CBS 'Numb3rs'

Brothers in Los Angeles, one a mathematical genius and the other an FBI agent, work together to solve crimes.

Source: The networks

In the age of comedians like
Stephen Colbert,
Jon Stewart
and
Wanda Sykes,
Mr. Leno's brand of humor is a throwback. He avoids partisan political jokes and punch lines that disparage any ethnic group or gender, and he rarely curses. He says he could never relate to comedians like
Lenny Bruce,
who was "always preaching to the converted," and cites Johnny Carson,
Bill Cosby
and
Jack Benny
as comedic role models. "Everyone says comedy has to be edgy. No, it just has to be funny," Mr. Leno says. His humor is a "big tent show" and he aims to put out "great food at sensible prices," he says.

"You watch '[Law & Order] SVU' and you don't want to go to bed after someone is horribly sexually violated so then you turn to 'CSI' and 'oh, here's a cerebral cortex, would you look at that,'" Mr. Leno says, speaking of the competition on TV at 10 p.m. "Let's just try some comedy."

Using a tactic he picked up as a teenager juggling jobs at McDonald's and a local Ford dealership, Mr. Leno lives off his earnings from doing stand-up and banks his NBC salary, he says. "It just keeps your head straight," he says. "In TV they can fire your ass at any minute for whatever reason. OK, I'll be in Vegas." NBC declined to discuss the details of Mr. Leno's contract but industry estimates put his salary at just under $30 million.

NBC, part of
General Electric
's
NBC Universal, hopes Mr. Leno's topical, wholesome humor can draw a wide audience. The audience for NBC's prime-time programs has declined 24% through the season ended in May from the same period in 2006, according to Nielsen Co. It recently put the network under the leadership of a company veteran, Jeff Gaspin, and programming executive Ben Silverman, after overseeing several expensive flops in his two years at the network, departed.

Creating "The Jay Leno Show" helped the struggling network hang onto Mr. Leno after it replaced him as host of "The Tonight Show" with Conan O'Brien this past June. "The Jay Leno Show" also cuts costs. Prime-time dramas typically average about $3 million to make an episode or $15 million a week to fill the 10 p.m slot. A live entertainment show like Mr. Leno's could cost as little as $2 million a week, according to industry estimates. NBC declined to discuss exact figures.

NBC's move sent shock waves through the industry, prompting some executives to criticize it as cost cutting that in the era of reality television further threatens high-quality original programming. Competing network executives have used the show as a way to promote their own expensive dramas by comparison. "NBC seems to be kind of doing their own thing and the other networks seem to be kind of following in the tradition of trying to put on great material,"
Stephen McPherson,
president of ABC Entertainment Group, recently told reporters.

NBC executives say they don't expect "The Jay Leno Show" to initially attract as many viewers as "CSI" or "Private Practice" but they predict Mr. Leno will catch up when competing networks air reruns. "We have 46 weeks of originals versus our competitors, are going to be doing 20 to 22 originals," says
Rick Ludwin,
executive vice president of late-night and prime-time series at NBC.

In an Internet survey conducted in April, NBC found that 71% of prime-time viewers said they would watch a 10 p.m. program that makes them laugh. And 74% said that a show on earlier at night would make it easier to catch Mr. Leno.

Much of Mr. Leno's deeply loyal following is among people older than TV's coveted 18 to 49 demographic. The median age of "Tonight Show" viewers when Mr. Leno was host was 55 years old, compared with 47 years old the first month Mr. O'Brien hosted the late-night show.

When NBC named Mr. Leno host of "The Tonight Show" in 1992, his mother suggested he change "The Tonight Show Starring Jay Leno" to "The Tonight Show With Jay Leno," a subtle change that Mr. Leno says made his modest mother more comfortable (" 'Oh, starring Mr. Big Shot,' " Mr. Leno imitates his mother,
Catherine Leno,
who died in 1993.). He says he fought, unsuccessfully, with the network about the title for the new prime-time show. Mr. Leno wanted to call it "The Weeknights With Jay Leno."

James Douglas Muir Leno is the son of an Italian-American insurance salesman and a Scottish immigrant housewife. He grew up in the town of Andover, Mass., often a source of his jokes. As a sophomore at Emerson College, Mr. Leno would drive to New York City on weekends to perform at comedy clubs. He sometimes slept outside an improvisational comedy club in Manhattan. By the 1970s, Mr. Leno performed more than 300 nights a year wherever he could: strip clubs, carnivals, casinos and coffee shops. He became known for his bushy hair, elongated chin, hyperactive work ethic, and array of jokes that poked clean-cut fun at everyday minutia.

Mr. Leno, 59 years old, and his wife, Mavis, an activist known for her work in Afghanistan, live in Los Angeles. He attends ribbon cuttings, shakes hands at airports and signs autographs at malls. He owns a house in Andover and says he regularly calls his high-school teachers and classmates to test out new jokes. The walls of his dressing room are decorated with a collage of letters and handmade Christmas cards from kids who appeared on the "Tonight" show. A framed thank you note in crayon from actress
Dakota Fanning
(age 9) perches above a mini-refrigerator stocked with bottled water.

Mr. Leno says he didn't go to another network after NBC replaced him on "The Tonight Show" because it would send the wrong message to his fans. "When I hear
Paula Abdul
complaining about $8 million…it just looks bad to real people," he says.

Even with all his performances this summer, Mr. Leno says he missed being on TV, if for no other reason than to poke fun at Republican Gov.
Mark Sanford
of South Carolina. "You tell your wife you're going for a walk and you go to Argentina?" he says, running his hand through his thick grey hair. "I wished I were on the air for that one," he sighs.

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